Subtract 72/40 from 18/90
1st number: 18/90, 2nd number: 1 32/40
18/90 - 72/40 is -8/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
18/90 = 18 × 4/90 × 4 = 72/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
72/40 = 72 × 9/40 × 9 = 648/360 - Subtract the two like fractions:
72/360 - 648/360 = 72 - 648/360 = -576/360 - After reducing the fraction, the answer is -8/5
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